﻿ Getting Started Tutorials - MechDesigner > Tutorial 14: Gear-Pairs / Rack-Pinions > A: Fixed Gear Centres > Reverted Gear-Train

# Reverted Gear-Train

### Reverted Gear-Pairs

 Schematic of Reverted Gear-Train. Reverted Gear Train: include: •two Gear-Pairs •two shafts •the input and output shafts are co-axial It is a Compound Gear with, two Gears-Pairs, and a special condition that makes the total number of teeth of the first gear-pair equals the number of teeth of the second-gear-pair, when the module is the same. The image to the left shows a schematic of a Reverted Gear-Train. There is more than one gear-pair, two shafts, and the input and output shafts are co-axial. Therefore, it agrees the definition of the Reverted Gear Train.

#### Reverted Gear Train – Stage 1

 Start with a Gear-Pair  - see Option 1 Step 14.1 •External Mesh •Number-of-teeth: T1=30, T2=70. The Gear Ratio is T1/T2 = 2.5 The total number-of-teeth is 100T.

#### Reverted Gear Train – Stage 2

 1.Mechanism-Editor: Edit the Base-Part 2.Part-Editor: Geometry toolbar: Add Line, Drag from the end-Point of the Line-of-Centers of Gear-Pair 1 3.Merge its start-Point with end-Point of the Line in Base-Part 4.Part-Editor: Add Dimension to the new Line. Exit Part-Editor. 5.Mechanism-Editor: Add a new Part. 6.Mechanism-Editor: Add Pin-Joint - click end-Point of new Line and origin new Part. Add the second Gear-Pair. 1.Mechanism-Editor: Add Gear-Pair 2.Add Gear-Pair: Line 1: Click the CAD-Line in the Driven Geared-Rocker as the first Gear-Pair 3.Add Gear-Pair: Line 2: Click the CAD-Line in the new Blue Part 4.Add Gear-Pair: Line 3 : Click the new Line and then the dimension of the Line. 5.Mechanism-Editor: Edit the Base-Part: 6.Part-Editor: Add Horizontal to the new Line. Exit Part-Editor. Video of Reverted Gears - Click to Play Edit the Gear-Pair 2 Edit the Number of Teeth: Gear 1 = 20 Gear 2 = 80 Video See Video to the left to see the gear reduction of the Gear-Pair. - Probably in error.